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Biomedical subjects

E O'Callaghan

Publications and source records attributed to E O'Callaghan.

At least 55 records · Page 3Linked to original sources
PubMed1997

The anthropometric assessment of dysmorphic features in schizophrenia as an index of its developmental origins.

BACKGROUND: Evidence suggests that schizophrenia may be a disorder with origins in early intrauterine mal-development. We have constructed a comprehensive anthropometric scale for the evaluation of dysmorphic features as an index of the nature and timing of developmental disturbance. METHOD: A detailed set of craniofacial and bodily measures was compiled and applied to 174 patients with schizophrenia and 80 matched control subjects. RESULTS: Patients had significantly higher scores on this scale and displayed multiple anomalies of the craniofacial region with an overall narrowing and elongation of the mid-face and lower face. Twelve craniofacial anomalies independently distinguished patients from controls and these variables correctly classified 95% of patients and 80% of control subjects. CONCLUSIONS: This new scale, while procedurally more exacting than the Waldrop scale, more clearly defines the topography of anomalies previously suspected in individuals with schizophrenia. These findings constitute direct evidence for disturbed craniofacial development in schizophrenia and indicate origins in the foetal period during which the characteristic human facial pattern evolves in close association with brain differentiation.

Abnormalities, Multiple↗
PubMed1997

Severity of alcohol dependence and its relationship to neurological soft signs, neuropsychological impairment and family history.

We examined the relationship between severity of alcohol dependence, subtle neurological impairment, neuropsychological deficits and genetic vulnerability among 36 day hospital attenders who satisfied the DSM-III-R criteria for alcohol dependence. Severity of alcohol dependence was unrelated to the presence of a family history, but was correlated with neurological soft signs and neuropsychological impairment. Neurological soft signs were correlated with neuropsychological impairment on both Trail A and Trail B. Patients with an affected first-degree relative exhibited more neurological soft signs. These data indicate that severity of alcohol dependence is related not only to neuropsychological impairment, but also to subtle neurological deficits which may not be apparent on conventional neurological examination. Patients with a positive family history of alcohol dependence may be particularly susceptible to the neurological sequelae of alcohol dependence, or may have neurological deficits which antedate their alcohol dependence.

Adult↗
PubMed1997

Obstetric complications and age at onset in schizophrenia: an international collaborative meta-analysis of individual patient data.

OBJECTIVE: An excess of obstetric complications in the histories of schizophrenic patients is a well-replicated finding, but less consistent results have been found concerning the relationships between obstetric complications and family history of schizophrenia, age at onset of schizophrenia, and gender. Small sample size limited the power of previous studies that attempted to assess such relationships. The aim of this study was to use data on individual patients from all available studies to examine the links between a history of obstetric complications and family history of schizophrenia, age at onset, and gender. METHOD: Raw data from 854 schizophrenic patients concerning history of obstetric complications rated according to the Lewis and Murray scale were obtained from 11 different research groups. Weighted average estimates were calculated with the use of regression techniques. RESULTS: A significant association was found between age at onset of schizophrenia and obstetric complications: the earlier the age at onset, the more likely the history of obstetric complications. Subjects with onset of schizophrenia before age 22 were 2.7 times more likely than those with onset at a later age to have had a history of abnormal presentation at birth and 10 times more likely to have had a history of complicated Cesarean birth. No association was found between obstetric complications and family history of schizophrenia or gender. CONCLUSIONS: The association between obstetric complications and early age at onset of schizophrenia indicates that the pathophysiology of early-onset schizophrenia involves neurodevelopmental impairment.

Adolescent↗
PubMed1996

Relationship between in utero exposure to influenza epidemics and risk of schizophrenia in Denmark.

Several recent epidemiological studies suggest that exposure to influenza during gestation increases the risk of later developing schizophrenia. Inconsistency exists, however, particularly in studies that have examined the relationship between the prevalence of influenza and the monthly number of schizophrenic births, over many years. Our sample (N = 9462) was obtained from a Danish computerized case register, and consisted of schizophrenia patients born between 1915 and 1970, and first admitted to Danish psychiatric hospitals between 1971 and 1991. The study sample was chosen to represent "incidence cases" to allow us to calculate the population attributable risk fraction (PAF). The temporal correlation of fluctuations in the prevalence of influenza and fluctuations in the monthly number of preschizophrenic births was examined using a Poisson regression analysis. Exposure to influenza 4 months prior to birth (i.e., about the 6th month of gestation) was significantly associated with an increased risk of later schizophrenia, especially for narrowly defined schizophrenia. The number of schizophrenic births was found to have risen by 12% (95% confidence interval: 1-24%) for every 100,000 cases of influenza in the 4th month before birth. Our model indicates the PAF to be 1.4%, that is, only 1.4% of the whole schizophrenic sample is attributed to prenatal exposure to influenza. Although maternal exposure to influenza during midgestation is not a major risk factor for schizophrenia, the elucidation of its causal mechanism may open the avenue to understanding the neurodevelopmental origins of the disease.

Adult↗
PubMed1996

Schizophrenia and neurological soft signs: gender differences in clinical correlates and antecedent factors.

Although it is recognized that patients with schizophrenia demonstrate more neurological soft signs (NSS) than control subjects, the significance and clinical correlates of these signs remain poorly defined. The present study examined 48 patients with DSM-III-R schizophrenia for evidence of NSS. The majority (98%) of patients demonstrated at least one NSS, although the range of scores was wide. There was no relationship between current dosage of neuroleptic medication and NSS score. Among males, there was a significant relationship between NSS and duration of illness. Males whose mothers experienced obstetric complications had higher NSS scores, while females with a family history of schizophrenia exhibited higher scores. These relationships in schizophrenia between NSS and factors of etiological importance wuch as obstetric complications and family history require further evaluation. The present findings are in accord with a body of evidence which suggests that gender may influence the impact of genetic and environmental factors on the neurology of the disorder.

Adolescent↗
PubMed1996

A case-control study of obstetric complications and later autistic disorder.

The precise etiology of autism remains unclear. Obstetric adversity has been described as one factor that may increase the risk for the disorder. We examined the contemporaneous birth records of 49 children satisfying DSM-III-R criteria for autistic disorder, at four Dublin maternity hospitals, using the previous same-sex live birth in that hospital as a control. Data were evaluated blind to subject status using two obstetric complication (OC) rating scales. No significant differences in obstetric adversity were found between index and control groups. Autistic individuals did not differ from controls in terms of previously described risk factors for this disorder (maternal age, maternal parity, birth order, and low birth weight) in autism. These data do not support the view that OCs increase the risk for later autism.

Adolescent↗
PubMed1996

Prenatal exposure to the 1957 influenza epidemic and adult schizophrenia: a follow-up study.

BACKGROUND: We investigated the hypothesis that prenatal exposure to the 1957 A2 influenza increases the risk of schizophrenia in adulthood. METHOD: We traced a cohort of individuals known to have been exposed to the 1957 influenza epidemic during gestation and an unexposed cohort matched for period of gestation and hospital of birth. Follow-up information on psychiatric illness in subjects was sought from two sources: maternal interview and psychiatric hospital admission data. RESULTS: Follow-up information was obtained on 54% of the sample: 238 subjects from the influenza-exposed group and 287 subjects from the unexposed group. There was no increased risk of schizophrenia among the exposed cohort compared to the unexposed cohort (relative risk 1.1; 95% Cl 0.41-2.95), although there was an increase in depressive illness (relative risk 1.59; 95% Cl 1.15-2.19). CONCLUSIONS: The association between prenatal influenza and an increased risk of schizophrenia in adulthood has thus far been found only in population-based data and is not supported by the present observational study which has information about exposure and outcome in individuals.

Cohort Studies↗
PubMed1995

Prevalence and correlates of mixed-handedness in schizophrenia.

Increased rates of nonright-handedness have been reported in schizophrenia, but a clear distinction has not been made between left- and mixed-handedness. Handedness preferences in 96 patients fulfilling DSM-III criteria for schizophrenia and 43 normal comparison subjects were assessed with the Edinburgh Handedness Inventory. A 100% criterion was used to establish left- and right-handedness. Results were analyzed with mantel-Haenszel odds ratios adjusted for age and sex. The schizophrenic group showed a significant increase in the proportion of mixed-handers compared with the normal group. There was no increase in pure left-handedness in the schizophrenic relative to the normal group. Mixed-handedness in the schizophrenic patients was significantly associated with chronicity of illness. Mixed-handed patients were less likely to have a family history of psychotic illness than patients with strong right- or left-handedness. The results indicate a neurodevelopmental rather than a genetic origin for anomalous lateralization in schizophrenia.

Adult↗
PubMed1995

The relationship of minor physical anomalies and other putative indices of developmental disturbance in schizophrenia to abnormalities of cerebral structure on magnetic resonance imaging.

Minor physical anomalies, together with obstetric complications, family history, and handedness status, were assessed to explore putative neurodevelopmental disturbance(s) in patients with schizophrenia whose cerebral structure had been examined previously by magnetic resonance imaging. Minor physical anomalies were related to negative symptoms in males and to premorbid intellectual function in females, but not to ventricular volume; however, three patients with evident neurodevelopmental anomalies of the ventricular system showed prominent minor physical anomalies. In exploratory analyses, obstetric complications were associated with left ventricular asymmetry, and a positive family history with inverse profiles of asymmetry in males vs. females; non-right-handedness was associated with increased ventricular volume in males but with poorer premorbid intellectual function in females. This nexus of relationships and their gender specificities suggest early dysmorphogenesis in schizophrenia that is related to sexual dimorphism.

Abnormalities, Multiple↗
PubMed1995

Does prenatal exposure to influenza in mice induce pyramidal cell disarray in the dorsal hippocampus?

Epidemiological studies point to an association between prenatal exposure to influenza and later schizophrenia. Such studies are consistent with neuropathologic reports demonstrating cytoarchitectural abnormalities in the hippocampus and parahippocampal gyrus suggestive of second trimester developmental anomalies. The hypothesis that prenatal exposure to influenza in the second trimester may induce hippocampal pyramidal cell disarray in mice was investigated. Between days 9-16 of pregnancy, 35 Balb/c mice were intranasally inoculated with either a mouse-adapted or non mouse-adapted pool of Influenza A/Singapore/1/57 (H2N2), and 10 controls were inoculated with normal saline. Offspring were sacrificed on day 21 postpartum. Microscopic examination of the CA1-CA2 junctional areas in the offspring of mice exposed to influenza failed to demonstrate excess pyramidal cell disarray when compared with influenza-free, age matched controls. There was evidence that disarray was greater among those exposed on day 13 of pregnancy. Analyses of the data by sex and severity of maternal infection failed to reveal any significant effects.

Animals↗
PubMed1995

Basal ganglia T2 relaxation times in schizophrenia: a quantitative magnetic resonance imaging study in relation to tardive dyskinesia.

Transverse, or spin-spin, relaxation times (T2) from magnetic resonance images of basal ganglia structures were compared between control subjects and patients with schizophrenia, who were subdivided on the basis of the presence or absence of tardive dyskinesia. As a group, schizophrenic patients showed evidence of somewhat more prolonged T2 relaxation times in the right putamen and globus pallidus than did control subjects; there were no significant correlations between hemispheric T2 values and corresponding volumes of the lateral ventricles. Overall, there was little difference in T2 values between patients with and without tardive dyskinesia. These data extend the range of evidence for basal ganglia dysfunction in schizophrenia, but they do not support earlier reports of prominent T2 changes associated with tardive dyskinesia.

Adult↗
PubMed1995

Prenatal exposure to influenza epidemics and risk of mental retardation.

This study was undertaken to determine whether prenatal exposure to influenza epidemics increases the risk of mental handicap. The monthly birth frequencies of 827 first-admission individuals (mean age at admission 13 years) with a primary diagnosis of non-specific mental retardation, discharged from psychiatric hospitals in England and Wales, were examined in relation to the monthly death rates from influenza over the period 1953-1980. The relative risk of developing mental handicap when exposed to influenza epidemics during mid-gestation was assessed by a generalized linear model. Increased death rates from influenza, a measure of prevalence of the infection, were significantly associated with an increase in births of mentally handicapped individuals 6 months later. For every 1000 female deaths from influenza there was a 17% increase in births of mentally handicapped individuals 6 months later. Maternal exposure to influenza at approximately the third to fourth month of gestation may be risk factor for developing mental handicap.

Adult↗
PubMed1995

Reproductive behaviour in schizophrenia relative to other mental disorders: evidence for increased fertility in men despite decreased marital rate.

Using case register data, the overall marital rate among 5158 patients with mental illness was found to be comparable to the general population. The proportion of those ever married was markedly reduced in the schizophrenic group relative to those with a manic or neurotic illness. Men with schizophrenia had a particularly low rate of marriage. The overall marital fertility of the 3 groups was comparable to each other and appeared to be higher than that in the general population. In the schizophrenic group only, married men, particularly those with a family history of mental disorder, produced more children than married women. Men might represent a more fertile group of schizophrenic patients with some biological advantage of increased fecundity, which may help to compensate for negative selection pressures.

Analysis of Variance↗
PubMed1995

Confinement of winter birth excess in schizophrenia to the urban-born and its gender specificity.

BACKGROUND: The season of birth phenomenon in schizophrenia was reexamined in relation to place of birth, in order to test the hypothesis that a seasonal factor might operate preferentially among those who were urban-born. METHOD: The seasonal distribution of births was examined among 3253 patients in two case registers having an ICD-9 diagnosis of schizophrenia and compared with the distribution of births among the normal population born in those catchment areas over the same period; those subjects born in population centres greater than 50,000 were defined as urban-born. RESULTS: Patients who were urban-born showed an excess of winter births relative to controls that was absent among their rural-born counterparts. On comparing patient groups, those who were urban-born were more likely to be born in the winter, while those who were rural-born were more likely to be born in the spring; this urban-rural distinction was confined essentially to female patients. CONCLUSIONS: These findings might be accommodated most readily in terms of a spatially as well as seasonally varying environmental factor that is associated with urbanicity and to which female offspring are more vulnerable.

Adult↗
PubMed1995

Tardive dyskinesia in schizophrenia. Relationship to minor physical anomalies, frontal lobe dysfunction and cerebral structure on magnetic resonance imaging.

BACKGROUND: It was hypothesised that schizophrenic patients with tardive dyskinesia show an excess of neurodevelopmental disturbance, particularly minor physical anomalies, in association with cognitive dysfunction and abnormalities of cerebral structure. METHOD: Forty-seven out-patients with a DSM-III diagnosis of schizophrenia were examined for tardive dyskinesia using the Abnormal Involuntary Movement Scale; they were examined also for minor physical anomalies and neuropsychological test performance. Cortical atrophy, signal hyperintensities and lateral ventricular volume were determined on magnetic resonance imaging. RESULTS: Patients with and without tardive dyskinesia could not be distinguished by age, gender distribution or a number of clinical measures; however, patients with tardive dyskinesia sorted fewer categories on the Wisconsin Card Sorting Test (P = 0.04). Cerebral structure in patients with and without tardive dyskinesia could not be distinguished on magnetic resonance imaging but those with dyskinesia, all of whom showed involvement of the orofacial region, showed more evident minor physical anomalies of the head relative to those of the periphery (P = 0.02). CONCLUSIONS: Tardive orofacial dyskinesia in schizophrenia appears to be associated particularly with poorer frontal lobe function, while predominance of craniofacial dysmorphogenesis may constitute a vulnerability factor that is related to the early origins of the disease process.

Adult↗